将泛型类型的Json转换为特定的Json格式

Question

我正在使用 Java 8，我尝试使用“Collectors.groupingBy”，但没有获得所需的格式public class ConsigneeLoadDetails {    private Integer tripID;    private String consignor;    private String consignee;    private String city;    private Double distanceToNext;    private Double load;    private Integer cap;    private Integer vehicleCapacity;    private Double cLoad;    private Integer truckUtilisation;    private Double latitude;    private Double longitude;      // getter , setter of all parameters }List<ConsigneeLoadDetails> listConsigneeLoadDetails = new ArrayList();// loop to add ConsigneeLoadDetailslistConsigneeLoadDetails.add(consigneeLoadDetails);我在 API 响应中低于 Json我想要以下格式的回复

Answer 1

你为什么不重新安排你的 POJO 类，像这样

public class ConsigneeLoadDetails {

    private Integer tripID;

    private String consignor;

    private Integer vehicleCapacity;

    private Double cLoad;

    private Integer truckUtilisation;

    private List<consigneeDetails> consigneeDetails    

    private Double latitude;

    private Double longitude;  

    // getter , setter of all parameters 

}

public class ConsigneeDetails {

    private String consignee;

    private String city;

    private Double distanceToNext;

    private Double load;

    private Integer cap;

    // getter , setter of all parameters 

}

Answer 2

Map<Integer, List<ConsigneeLoadDetails>> collect =

// group the object by id   

listConsigneeLoadDetails.stream().collect(Collectors.groupingBy(consigneeLoadDetails -> consigneeLoadDetails.tripID));

        List<ConsigneeLoadDetailsDto> dtoList = new ArrayList<>();

        collect.forEach((integer, consigneeLoadDetails) -> {

            List<ConsigneeLoadDetails> list = consigneeLoadDetails;

            if (Optional.ofNullable(list).isPresent() && !list.isEmpty()) {

                ConsigneeLoadDetailsDto dtos = new ConsigneeLoadDetailsDto();

                dtos.setTripID(integer);

                dtos.setConsignor(list.stream().findFirst().get().getConsignor());

                dtos.setVehicleCapacity(list.stream().findFirst().get().getVehicleCapacity());

                dtos.setCLoad(list.stream().findFirst().get().getCLoad());

                dtos.setTruckUtilisation(list.stream().findFirst().get().getTruckUtilisation());

                List<ConsigneeDetails> consigneeDetails = new ArrayList<>();

                list.forEach(next -> {

                    ConsigneeDetails con = new ConsigneeDetails();

                    con.setCap(next.getCap());

                    con.setCity(next.getCity());

                    con.setConsignee(next.getConsignee());

                    con.setDistanceToNext(next.getDistanceToNext());

                    con.setLoad(next.getLoad());

                    consigneeDetails.add(con);

                });

                dtos.setConsigneeDetails(consigneeDetails);

                dtoList.add(dtos);

            }

        });

// Your result will be store in 

// dtoList

    }

}

@Getter

@Setter

@ToString

class ConsigneeLoadDetailsDto {

    private Integer tripID;

    private String consignor;

    private Integer vehicleCapacity;

    private Double cLoad;

    private Integer truckUtilisation;

    private List<ConsigneeDetails> consigneeDetails;

}

@Getter

@Setter

@ToString

class ConsigneeDetails {

    private String consignee;

    private String city;

    private Double distanceToNext;

    private Double load;

    private Integer cap;

}